Capture and release of acid gasses using tunable organic solvents with binding organic liquids

Abstract

A class of water lean, organic solvents that can bind with various acid gasses to form acid gas bound molecules having a high degree of intramolecular hydrogen bonding which enables their use as regenerable solvents for acid gas capture. Unlike the other devices described in the prior art, the present invention takes advantage of shortened distances between the portions of the molecule that form hydrogen bonds within the structures when loaded with an acid gas so as to create a molecule with a higher internal bonding affinity and a reduced proclivity for agglomeration with other molecules.

What is claimed is: 
     
       1. A method for capturing an acid gas from a stream containing said acid gas the method comprising the step of contacting the stream with a gas selective capture sorbent comprising a 1-BEIPADIP-2-BOL that reversibly binds an acid gas under a first set of conditions and releases said acid gas under a second set of conditions, whereby the acid gas binds to the gas selective capture sorbent to form a bound solvent. 
     
     
       2. The method of  claim 1  further comprising the step of moving the bound solvent to another location and exposing said bound sorbent to a second set of conditions whereby the acid gas is released and the sorbent is regenerated. 
     
     
       3. The method of  claim 1  wherein the sorbent is a liquid. 
     
     
       4. The method of  claim 1  wherein the acid gas is selected from CO 2 , SO 2 , COS, CS 2 , H 2 S, and combinations thereof. 
     
     
       5. The method of  claim 1  wherein the step of exposing said bound sorbent to a second set of conditions includes heating said sorbent to a temperature between from 100° C. to 130° C. 
     
     
       6. The method of  claim 1  wherein the second set of conditions includes heating a bound sorbent in the presence of an antisolvent in the liquid phase to a temperature between from 70° C. to 100° C. 
     
     
       7. The method of  claim 6  wherein the antisolvent is a non-volatile, chemically inert liquid with low polarity. 
     
     
       8. The method of  claim 1 , wherein the contacting under a first set of conditions forms a zwitterionic alkylcarbonate, and wherein the step of exposing said acid gas bound sorbent to a second set of conditions includes shifting polarity of the sorbent from zwitterionic alkylcarbonate form to an alkylcarbonic acid form.